1 . 某物理兴趣小组的同学们做“金属丝电阻率的测量”实验,已知金属丝的电阻大约为,具体实验操作如下:
(1)小明首先用螺旋测微器测量金属丝的直径。
(2)小刚取来两节新的干电池、开关和若干导线及下列器材:
A.电压表,内阻约
B.电压表,内阻约
C.电流表,内阻约
D.电流表,内阻约
E.滑动变阻器,最大阻值为
F.滑动变阻器,最大阻值为
①要求较准确地测出其阻值,电压表应选
②实验中小华同学的实物连线如图所示,请指出小华实物连线中的两处明显错误。
错误a:
错误b:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37d65e051e943ab28fa57aee2fb57994.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37d65e051e943ab28fa57aee2fb57994.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/22/d1f08c63-45cd-4ca3-acfa-f7590ffbf088.png?resizew=285)
(1)为了研究导体电阻与横截面积的关系,应选择
(2)若要测量BC段金属丝的电阻,试在图甲中以笔画代替导线完成电路图连接。
(3)为了测量镍铬合金的电阻率,用螺旋测微器测量BC段金属丝的直径D,如图乙所示,调节过程中,螺旋测微器上三个部件A、B、C使用的先后顺序应该为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a6d85799453899836bc34ad276ec80e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/22/a339f422-ee86-4c76-888d-853158405f6e.png?resizew=629)
(4)图丙为实验所用的电流表和电压表的表盘,电压表选用0-3V量程,电流表选用0-0.6A量程。将电压表一端接在B点,另一端接在BC段金属丝的P点(图中未画出),测出电压U和PB之间的距离d、改变P点位置多次测量,获得一系列U、d数据并画出
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6a3d4361f9e6d47b6d44487278f1c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c41f0c83dd726b5373dee0e8e1ab4aeb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92e2554579f1bed7f3f42b873da9b43a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/644a7a82d8e238066fc4590deb7ebda1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d630a705f099d5c3a6d1f5bc706a801.png)
(1)该同学用米尺测得铜线的长度为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83f6fe99e5a303292cf5831200ea16c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f3bf70722b22983c120d008d097602.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/14/8d9891b6-faa3-45a3-a70d-316da7b82bb0.png?resizew=132)
(2)设计如图2的电路图测定钢丝电阻
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2581ae160692cd7e2686226fe5e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/910f1655703721b51006b887a2394b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/779629f16056a50f4c06e3996d8e1c82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efc18a5bb2e53586331b2a58538a48b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84abbfb85a00f48b5db11eeb76b8d134.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/779629f16056a50f4c06e3996d8e1c82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19f20f21a9d50b61dac519a3ddab539d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84abbfb85a00f48b5db11eeb76b8d134.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2581ae160692cd7e2686226fe5e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efc18a5bb2e53586331b2a58538a48b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19f20f21a9d50b61dac519a3ddab539d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/14/919de5a9-6a34-49a3-bd8b-a5a3a088e86c.png?resizew=239)
(3)已知电流表示数为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84abbfb85a00f48b5db11eeb76b8d134.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19f20f21a9d50b61dac519a3ddab539d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0bdc68d2f849ba231ec365c3e479a7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04bd482c8aa483cd59b4c22636960fe0.png)
(4)请提出一条提高测量精度的建议
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
A.电池组(3V,内阻约1
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
B.电流表A1(0~3A,内阻0.0125
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
C.电流表A2(0~0.6A,内阻约0.125
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
D.电压表V1(0~3V,内阻4k
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
E.电压表V2(0~15V,内阻15k
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
F.滑动变阻器R1(0~20
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
G.开关、导线若干
(1)上述器材中,电流表应选
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/10/bce63b21-2675-4570-b088-6c1ff0215dbc.png?resizew=379)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/10/49bc8f3c-1f8c-4f6d-8535-afdb55779d28.png?resizew=153)
(2)若用螺旋测微器测得金属丝的直径d的读数如图,则读为
(3)若用L表示金属丝的长度,d表示直径,测得电阻为R,请写出计算金属丝电阻率的表达式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/171102a883b22fe6ca578efc8926f5b8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/4/06f857c7-6a6c-493b-b43b-a0dd732cd934.png?resizew=681)
(1)用螺旋测微器在电阻丝上的三个不同位置测出电阻丝直径,求出平均值D;若螺旋测微器某次测量结果如图丙所示,其示数为
(2)根据电路图甲,连接实物图乙,请帮助他们把电路图补充完整。
(3)调节电阻丝上导电夹P的位置,用毫米刻度尺测量并记录导电夹P到电阻丝右端B的长度x;闭合开关S,记录电压表示数U、电流表示数I;
(4)改变电阻丝上的导电夹P的位置,重复步骤(3),记录多组x、U、I的值。
(5)根据多组测量得到的实验数据绘出
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b5d5f2b925044fa13e4bd59496a4625.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b30db97c39edcede2f0e7d4e075fecec.png)
(1)该同学先用万用表粗略测量容器内水样的电阻。当选择欧姆表“×1k”挡时,发现指针偏转角度过小,该同学应换用
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/25/85844562-cc15-4181-8a22-8b9f053a8d00.png?resizew=445)
(2)接下来该同学用伏安法尽量准确地测量容器内水样的电阻。除开关和若干导线外,他还找到以下器材:
A.电源E:电动势约为15.0V,内阻不计;
B.电压表V1:量程0~3V,内阻约3kΩ;
C.电压表V2:量程0~15V,内阻约15kΩ;
D.电流表A1:量程0~0.6A,内阻约0.1Ω;
E.电流表A2:量程0~200μA,内阻约500Ω;
F.滑动变阻器R1,总阻值约10kΩ;
G.滑动变阻器R2:总阻值约100Ω;
①实验中选择的器材有
②图丙中已画出部分电路设计图,请补充完整,并标明所用器材的代号
![](https://img.xkw.com/dksih/QBM/2023/7/24/3287766128205824/3287896277417984/STEM/1219f75e6b474627ae9cfdbf15d30be3.png?resizew=152)
③测出水样的电阻Rx后,为了测出样品的电导率σ,请写出该同学还测量出管的内径D,可求出样品的电导率σ=
A.电源(电动势约为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc2b2c17a78210bcee15917ed1101102.png)
B.待测电线(长度约
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f631cfdf4666db95beb923072ced8d95.png)
C.电流表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/024e2379c58191758f8bd7602a6bcb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e504d00fa6b11168d2b9a353868c636.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2858005b9ae89ae080d83dcc13cf8e81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ac2aa4ec55c8857efd709b13691c82c.png)
D.电流表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b34a75c2a392f235c5f07b91d9fb58d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/469015d5fd7b688977dbd268cd930a56.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8cc7abc1dd02479f3bdb01941fe4ff3.png)
E.滑动变阻器
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efc18a5bb2e53586331b2a58538a48b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6f7b44014883510d3933bf20d66f44f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9840b5fa02cea57ef450c0ccb31eded2.png)
F.开关、导线若干。
(1)实验小组成员先用螺旋测微器测量该材质电线的直径
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c98c59cd4749afdd21e73529fc84323.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f3bf70722b22983c120d008d097602.png)
(4)根据以上数据可以估算出这捆电线的电阻率
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/171102a883b22fe6ca578efc8926f5b8.png)
A.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20269fcddd433a14255a1de1be7e24d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f92e7e0eab07c0859ae8516b0be96b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00b7551f6bf97278d9aa7efc82bde559.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e34330a09d33c970163a5d4a6452452.png)
(1)用毫米刻度尺测量接入电路中的金属丝的有效长度L,再用螺旋测微器测量金属丝的直径D。某次测量结果如图1所示,则这次测量的读数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a6d85799453899836bc34ad276ec80e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/13/701f8c94-1e50-4726-bd2f-19af27b56049.png?resizew=138)
(2)用多用电表测得金属丝的阻值为3Ω,现在使用电流表和电压表准确测量金属丝的阻值。为了安全、准确、方便地完成实验,除电源(电动势为4V,内阻很小)、待测电阻丝、导线、开关外,电流表应选用
A.电压表V2(量程3V,内阻约3kΩ)
B.电压表V1(量程15V,内阻约15kΩ)
C.电流表A1(量程600mA,内阻约1Ω)
D.电流表A2(量程3A,内阻约0.02Ω)
E.滑动变阻器R1(总阻值10Ω,额定电流2A)
F.滑动变阻器R2(总阻值100Ω,额定电流2A)
(3)若采用图2所示的电路测量金属丝的电阻,电压表的左端应与电路中的
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/13/baaeaa25-1155-41e1-8fdb-6da627d0a478.png?resizew=189)
(4)若采用图3的电路测量电阻率,图中的电流表内阻跟R0接近。闭合开关S,多次移动滑片P的位置改变电路中接入金属丝的有效长度,分别记录每次电流表的示数I和接入电路中金属丝的有效长度L。根据实验中所测的数据,作出的下列图像合理的是
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/13/d7a46cf1-eed8-472e-b232-f3e325c1011c.png?resizew=207)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/13/49874b31-b77b-47bc-8084-0682f43cea7b.png?resizew=582)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/442257676ca155e57db46b636bd32845.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/29/709e44cd-9b74-491a-b866-d8484da76d9a.png?resizew=321)
金属丝的电阻大约为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec9333c48b31195c71f539b972a98d68.png)
直流电源:电源电压
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41d8b94b084bbad77f6571673d8ccc19.png)
电流表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ae396d2cf4277c0a9b542c50c9797e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b5c929172bbfc21741fa7ef1f53b7bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d44d033bbc7752424cc86ae17a748e4.png)
电流表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16dde22198470685960ad27c5ed51aef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/881cf9cbfbbf7bb84f8ca2f3db9ca2f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/159faf4a64cab518863177238d345ff7.png)
电压表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7365bea3ff759954688d89542e33679c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a6bb65878785532d817f8fd11a9ef3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/951f5dfc2ee88b950c0a4322d9236ce4.png)
滑动变阻器
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffad6f2a53419f27e944abeca546a208.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9fd79de5050f5960c9478154c48e830.png)
滑动变阻器
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c89d69690afac14573ca7ade0445551a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6e278c32ede0c61f56cb6c0dc50dc29.png)
开关、导线等。
(1)从甲中读出金属丝的直径
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a6d85799453899836bc34ad276ec80e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f3bf70722b22983c120d008d097602.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a6d85799453899836bc34ad276ec80e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f3bf70722b22983c120d008d097602.png)
(2)在所给的器材中,应选的电流表是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd995178601c2ad7b40f973d268c7bb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04582116cd765fcc5a52f44279ad6c94.png)
(3)根据题目要求,将下面实验电路图补充完整
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/29/7c84554e-fce7-423b-801f-687e474b703e.png?resizew=121)
(4)用待测金属丝的电阻
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2581ae160692cd7e2686226fe5e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c88d9142df6ba8e43c1a93bd04a1362.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b30db97c39edcede2f0e7d4e075fecec.png)
(5)实验测出的金属丝的电阻为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80c2b1f221e3b68fc52e7484210e1515.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9942091e83e1d59af01f499a0caee212.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86ebba6ed1add0fe647c0226614b9290.png)
10 . 在做测定金属的电阻率的实验中,若待测电阻丝的电阻约为5Ω,要求测量结果尽量准确,备有以下器材:
A.电池组(3V,内阻r=1Ω)
B.电流表(0~3A,内阻约0.0125Ω)
C.电流表(0~0.6A,内阻约0.125Ω)
D.电压表(0~3V,内阻约4kΩ)
E.电压表(0~15V,内阻约15kΩ)
F.滑动变阻器(0~20Ω,允许最大电流1A)
G.滑动变阻器(0~2000Ω,允许最大电流0.3A)
H.开关、导线
(1)上述器材中应选用的是
(2)在本实验中,某同学用游标卡尺和螺旋测微器测该电阻丝的长度L和直径d。
(3)实验电路应采用如图所示哪个
(4)接通开关,改变滑动变阻器滑片P的位置。并记录对应的电流表示数I,电压表示数U。
(5)本实验所用电路,产生误差的主要原因是
A.电流表测量值小于流经Rx的电流值
B.电流表测量值大于流经Rx的电流值
C.电压表测量值小于Rx两端的电压值
D.电压表测量值大于Rx两端的电压值
(6)用实验过程中测量的物理量对应的字母表示电阻率,则该圆柱复合材料电阻率的表达式为=